Lapping machine



Feb. 24, 1931. w N 1,793,486

LAPPING MACHINE Filed May 5, 1927 5 Sheets-Sheet 1 BY WMW $14 ATTORNEY.

Feb. 24, 1931.

w. P. HUNT LAPPING MACHINE Filed May 5, 1927. s Sheets- Sheet 2 V mm BY945% 71. 9m

[ 4). ATTORNEY.

Feb. 24, 1931.

. w. P. HUNT LAPF RNG MACHINE 1927 3 Sheets-Sheet 3 I Viv/ll Filed May5,

M A TTORNEY.

Patented Feb. 24, 1931 UNITED STATES IATENT OFFICE WILSON r. HUNT, ormoLmE, ILLInoIs, ASSIGNOR" ro MOLINE TOOL COMPANY, 013* MOLINE,ILLINOIS, A CORPORATION I LAIPIN G MACHINE Application filed flay 5,

provide each of the tools with a set of grinding elements which arecapable of expansion, together with means for a gradual expansionthereof, so as to correspondingly increase the cutting capacity of thetool. The operating means therefor is so arranged as to cause avariation in the position of the grinding elements upon eachreciprocationof the tool.

other purpose thereof is to provide means for a delicate adjustment ofthe expansion devices, so that the difierent sets of grinding tools maybe brought to the same diameter when desired, or one or other of saidtools may be independently adjusted to conform to the size of the boreof the cylinder in which it is to be used. There is at times a variationin the diameters of such bores.

The above named, and other features and advantages of the invention willmore fully appear from the following specification, in-

which;

Fig. 1 is a front elevation of a lapping machine of a commonconstruction, with the invention applied thereto.

Fig. 2 is a fragmentary side view showing the operating mechanism forthe reciprocating. head of the machine, and the invention supportedthereon.

Fig. 3 is a cross-section of one of the grindingtools.

.Fig. 4 is an enlarged detail of the invention,

in partial longitudinal section.

Fig. 5 shows the cam and ratchet ofFig. 4 rotated through 180.

The embodiment of the device as set out herein shows the same as appliedto a lapping machine of a four spindle formation, it being understoodthat the same is usable with le machines, such.

movement to'give to the tools 192'7. Serial No. 188,957.

any .number of spindles and tools connected therewith, and the same hasan independent application to and operation of each of such tools.

The reference number 1 indicates the base of a machine of the typenamed, on which is a table 2 for the support of an engine block or otherwork to be' operated upon. Mounted above the table is a frame 3, on theface of which is a pair of vertical ways 4 upon which is carried atraveler 5. Fixed to said traveler is a cross-beam 6,.upon which aremounted housings 7, in which are rotatably supported spindles 8, fixedto the lower ends of which are grinding tools 9. Supports 10 areprojected upwardly from the side pieces of the frame 3, in which isrockingly mounted an arm 11, the forward end of which is connected by acoupling 12 with the traveler 5. Movement may be imparted to the rearend of said arm in any known manner for giving to the traveler and partsmounted thereon a desired amount of vertical reciprocating movement.

Fixed to each of the spindles 8 is a worm pinion 13, adapted foroperation from a worm drive 14 on a shaft 15 rotatablymounted in thecross-beam 6. On one end, of said shaft is a pulley 16 to which a rotarymovement may be imparted for giving a similar movement to the shaft.

In the lower end of each of the spindles 8 is a bushing 17 in which isrotatable a rod 18,

which pro ects upwardly through the spin dle, and for a little distanceabove the same. Said rod is held normally in an elevated position bymeans of a coiled spring 19 in a recess-20 in the upper end of thespindle, the upper end of the spring bearing againsta pin in the rod. Inthe lower ends of the rods are pins 21 entering openings in the innerfaces of grinding stones 22, four of which are provided for each of thetools 9, as shown herein.

'At their rear edges said stones are provided with flanges '23, operable,in ways 24 in the body of the tool, such ways being inclined downwardlyand outwardly, so that a downward movement of the pins 21 will move thestones 22 downwardly, and at the same time the stones will movegradually outwardly.

Upon a return moiement of the pins the ets 26 fixed to the traveler 5,in proximity to the upper ends of thespindles 8, and fixed to said shaftso as to project above the upper ends of each of the rods 18 is a seriesof arms 27, each of which is fitted in its forward end with a threadedopening adapted to receive a similarly threaded screw 28, provided atits upper end with a thumb turn 29, by means of which the position ofthe screw may be regulated. Just below the thumb-turn is a barrel 30,containing 'micrometer markings which are readablewith a pointer 31,fixed to the arm 27. a

To one end of the shaft 25 is fixed an arm 32, in the upper end of whichsecured a pin 33, provided with a roller for operation on the edge: of acam wheel 34, rotatable with a shaft 35 mounted in a bearing 36 fixed tothe face of the traveler 5. A ratchet-wheel 37 is also fixed to theshaft 35, the teeth of said ratchet-wheel being engaged; by a dog 38pivoted in a bracket 39 attached to the frame 3. In the operation of themachine the shaft 25 and wheels thereon have avertical reciprocatingmovement with the traveler 5, whereas the dog 38 is stationary. As aresult the up and down movement of the ratchet wheel will cause anengagement of the dog 38 with the teeth .of said wheel in succession,and each of said movements will be accompanied by a partial rotation ofthe ratchet wheel and shaft 35. The conformation of the cam wheel 34 issuch as to move the upper endof the arm 32' outwardly, which movement isimparted to the arm 27,- causing the screw 28 i to force the rod 18downwardly, resulting in the expansion of the grinding elements beforereferred to. 5 At one point in the edge of the cam wheel 34 is anoff-set 40, which permits a reverse movement of the arm 32 and aconsequent immediate collapse of the grinding elements. This takes placeat the end of the operation on a particular piece of work, such as acylinder, and when the tool 9 is at the lowest part of its stroke; Thereturn movement of the tool upwardly is thereby accomplished without anyengagement with the wall of the cylinder;' and with no danger of thecylinder wallbeing scratched or otherwise marred in v the last movementof the tool outwardly, as

is liable to happen with non-collapsible tools;

It is the purpose of the invention'to have the cam-wheel 34; describe acomplete revolution foreach operation of the tool, the numof teeth inthe ratchet wheel correspondmg with the number of reciprocations of theits tool for'such operation, and said cam wheel is formed graduallyincreasing radii from the inner end of the 'ofl-set 40 to the outer endthereof, except for a little distance on the edge of the cam at 41,which has the same radius, and which permits the last reciprocatingmovement of the tool in the cylinder to be made without any farther expansion of the grinding'elements. Bythis means one or more finishingstrokes can be given to the tool. 1

The rod 18 is normally positioned at its highest point in the spindle,with the tool 9 'at its lowest'diameter, and as the work proceeds therod is forced gradually downwards,

expanding the grinding stones as before men-' tioned. -The initialposition of the rod can be varied, by adjustment of the screw 28, toconform to variations in thesize of the bore of a cylinder, such as.frequently occurs in practice: In manycases the size of the bore is lessthan the requirements, and to permit the grinding tool to conformthereto it can be reduced'in diameter to less than the normal provision.After the proper adjustments, if any, are made, the tools of one machineall operate c'oincidently and independently, and if it is desired toproportionately increase the diameter-pf any particular cylinder thiscan beaccomplished by adjustment of the micrometer screw of the toolthat is operating therein. f

Some machines of the mentioned are provided with means for interrupting"the movement 'of lapping mechanism at the end I of a predeterminednumber of movements thereof, and the movements of the controllingdevices set forth herein can be synchronized therewith, so that" thelapping tools willbe collapsed andwithdrawn from the cylinder andsupports thereof.- Applicant does not tion set forth herein; as changescan be made in the form and arran' would still be t e scope of theinvention. 1 I f p What I.claim, and desire to secure by Letters Patent,is: 1. In combination with a main frame and mechanism supported thereonso as to be re-. ,ciprocable, a spindle rotatably mountedinsaidmechanism, a tool 'carried y provided with exp'ansible gelements andmeans for the gradua expansion of sad grinding elements duringapredetermined v. 2. In combination witha and frame'mounted thereoii'so.as to recipro wish to be understood as limiting his device {to the exactconstruc-' the spindle cut thereof which ,120 -nu mber of movements, ofsaid mechanism, said 'means including means for permitting 'cate,a'spindl'e' rotatably;;mounted in said 7 last-named frame, a'toohcarriedby said spindle provided with ansible elements, a cam- ,wheel carried bysaid a part operated thereby during the operation of said frame, meansfor imparting the movement of said part to said expansible elements, tocause a gradual expansion thereof, and means for actuating saidcam-wheel during the operation of said frame.

3. In combination with a stationary frame, and frame mounted thereon soas to reciprocate, a tool rotatably mounted in said lastnamed frame, andprovided with expansible elements, a cam-wheel carried by saidvlastnamed frame, and a part actuated thereby, said cam-wheel having atrack with a gradually increasing. radius, means for imparting themovement of said part to said expansible elements, and means forrotating said camwheel coincidently with the movement of said last-namedframe.

4. In combination with a stationary frame and frame movably mountedthereon, a tool rotatably mounted in said movable frame, and providedwith expansible operating elements, a cam-Wheelcarried by said movableframe, and lever actuated thereby, said cam-,

wheel having a track with a gradually increasing radius and off-set atone point therein, means for imparting the movement of said lever tosaid expansible elements, and means for giving a, complete rotarymovement to said cam-wheel coincldently with the movement of saidlast-named frame, the conformation of said track causing a gradualspreading of said expansible elements, and the off-set in said trackpermitting the collapse of said expansible elements at the end of themovement of said cam-wheel.

5. In a device of the class described, a suitably supported toolprovided with expansible elements, a controlling member for said.expansible elements, a cam-wheel and lever actuated thereby, said leverbeing operatively connected with said controlling member, said cam-Wheelhaving a track of gradually increasing radii, an ofi-set portion, and anintermediate part adjacent to said off-set portion which imparts nomovement to said lever, and means for imparting to said cam-wheel a.predetermined number of intermittent movements.-

6. v In combination with a stationary frame and frame mounted thereon soas to reciprocate, a spindle rotatably mounted in said last-named frameand tool on one end thereof provided with expansible working elements, arod member extending through said spindle and operatively connected withsaid Work-' ing elements, a. cam-wheel on saidmovable frame and leveractuated thereb and opera- I 7. In combination with a main frame andWILSONP. HUNT.

tively connected with said to a 'ratchet- 7 wheel adapted for rotationwith said camwheel, and a detent on the main frame for operation withthe teeth of said ratchetwheel, said ratchet wheel being adapted to giveto the cam-wheel a predetermined number of intermittent. movements.

